The present invention relates to combustion engines, and more particularly to rotary engines including engines having sliding vane rotors.
Rotary gas devices such as compressors, motors, and engines are known in the prior art as alternatives to corresponding reciprocal piston-type machines. Traditionally the rotary devices have avoided the problems associated with reciprocating mechanisms; however, rotary engines have not been widely used because they are particularly subject to ineffective sealing and lubrication and consequent excessive wear and foreshortened useful life.
Apart from the well known disadvantages of reciprocating mechanisms, a relatively recently recognized disadvantage of piston engines is characterized by the traditional Otto cycle wherein combustion mainly occurs at constant volume, producing very high pressures and temperatures and consequent significant air pollution by emissions of No.sub.x. Accordingly, some continued development of rotary engines has been directed to reducing harmful emissions by limiting combustion temperatures and pressures. For example, U.S. Pat. No. 3,961,485 to Wiley discloses a vane type rotary engine using exhaust from a multichamber Otto cycle engine to power a Sterling cycle engine on the same shaft. Nevertheless, rotary engines remain without widespread acceptance. It is believed that factors contributing to this situation include the excessive complexity of known antipollution rotary engines and continuing problems with sealing and wear.
Thus there is a need for a combustion engine that overcomes the disadvantages of the prior art.